| Resolution (Bits) | 12 |
| Number of input channels | 8 |
| Sample rate (Max) (kSPS) | 52 |
| Interface type | SPI |
| Architecture | SAR |
| Input type | Differential, Single-Ended |
| Multi-channel configuration | Multiplexed |
| Rating | Catalog |
| Reference mode | Ext, Int |
| Input range (Max) (V) | 5.5 |
| Input range (Min) (V) | 0 |
| Features | Oscillator, PGA |
| Operating temperature range (C) | -40 to 85 |
| Power consumption (Typ) (mW) | 6 |
| Analog voltage AVDD (Min) (V) | 2.7 |
| Analog voltage AVDD (Max) (V) | 5.5 |
| INL (Max) (+/-LSB) | 2.5 |
| Digital supply (Min) (V) | 2.7 |
| Digital supply (Max) (V) | 5.5 |
- PGA Gains: 1, 2, 4, 5, 8, 10, 16, 20V/V
- Programmable Input (Up to 4-channel Differential/Up to 8-channel Single-Ended or Some Combination)
- 1.15-V, 2.048-V or 2.5-V Internal Reference
- SPI/DSP Compatible Serial Interface (≤20 MHz)
- Throughput Rate: 52 kSamples/sec
- Error/Overload Indicator
- Programmable Output 2s Complement/Binary
- 2.7-V to 5.5-V Single-Supply Operation
- 4-Bit Digital I/O Via Serial Interface
- Pin Compatible With ADS7871
- SSOP-28 Package
- APPLICATIONS
- Portable Battery-Powered Systems
- Low-Power Instrumentation
- Low-Power Control Systems
- Smart Sensor Applications
QSPI and SPI are trademarks of Motorola, Inc.
Microwire is a trademark of National Semiconductor Corporation.
All other trademarks are the property of their respective owners.
The ADS7870 (US patents 6140872, 6060874) is a complete low-power data acquisition system on a single chip. It consists of a 4-channel differential/8-channel single-ended multiplexer, precision programmable gain amplifier, 12-bit successive approximation analog-to-digital (A/D) converter, and a precision voltage reference.
The programmable-gain amplifier provides high input impedance, excellent gain accuracy, good common-mode rejection, and low noise.
For many low-level signals, no external amplification or impedance buffering is needed between the signal source and the A/D input.
The offset voltage of the PGA is auto zeroed. Gains of 1, 2, 4, 5, 8, 10, 16, and 20 V/V allow signals as low as 125 mV to produce full-scale digital outputs.
The ADS7870 contains an internal reference, which is trimmed for high initial accuracy and stability vs temperature. Drift is typically 10 ppm/°C. An external reference can be used in situations where multiple ADS7870s share a common reference.
The serial interface allows the use of SPI?, QSPI?, Microwire?, and 8051-family protocols, without glue logic.
